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R A Foley

Publications and source records attributed to R A Foley.

5 recordsLinked to original sources
PubMed2001

The phylogeography of Y chromosome binary haplotypes and the origins of modern human populations.

Although molecular genetic evidence continues to accumulate that is consistent with a recent common African ancestry of modern humans, its ability to illuminate regional histories remains incomplete. A set of unique event polymorphisms associated with the non-recombining portion of the Y-chromosome (NRY) addresses this issue by providing evidence concerning successful migrations originating from Africa, which can be interpreted as subsequent colonizations, differentiations and migrations overlaid upon previous population ranges. A total of 205 markers identified by denaturing high performance liquid chromatography (DHPLC), together with 13 taken from the literature, were used to construct a parsimonious genealogy. Ancestral allelic states were deduced from orthologous great ape sequences. A total of 131 unique haplotypes were defined which trace the microevolutionary trajectory of global modern human genetic diversification. The genealogy provides a detailed phylogeographic portrait of contemporary global population structure that is emblematic of human origins, divergence and population history that is consistent with climatic, paleoanthropological and other genetic knowledge.

Africa↗
PubMed1998

Towards a theory of modern human origins: geography, demography, and diversity in recent human evolution.

The origins of modern humans have been the central debate in palaeoanthropology during the last decade. We examine the problem in the context of the history of anthropology, the accumulating evidence for a recent African origin, and evolutionary mechanisms. Using a historical perspective, we show that the current controversy is a continuation of older conflicts and as such relates to questions of both origins and diversity. However, a better fossil sample, improved dates, and genetic data have introduced new perspectives, and we argue that evolutionary geography, which uses spatial distributions of populations as the basis for integrating contingent, adaptive, and demographic aspects of microevolutionary change, provides an appropriate theoretical framework. Evolutionary geography is used to explore two events: the evolution of the Neanderthal lineage and the relationship between an ancestral bottleneck with the evolution of anatomically modern humans and their diversity. We argue that the Neanderthal and modern lineages share a common ancestor in an African population between 350,000 and 250,000 years ago rather than in the earlier Middle Pleistocene; this ancestral population, which developed mode 3 technology (Levallois/Middle Stone Age), dispersed across Africa and western Eurasia in a warmer period prior to independent evolution towards Neanderthals and modern humans in stage 6. Both lineages would thus share a common large-brained ancestry, a technology, and a history of dispersal. They differ in the conditions under which they subsequently evolved and their ultimate evolutionary fate. Both lineages illustrate the repeated interactions of the glacial cycles, the role of cold-arid periods in producing fragmentation of populations, bottlenecks, and isolation, and the role of warmer periods in producing trans-African dispersals.

Animals↗
PubMed1991

Ecology and energetics of encephalization in hominid evolution.

Hominid evolution is marked by very significant increase in relative brain size. Because relative brain size has been linked to energetic requirements it is possible to look at the pattern of encephalization as a factor in the evolution of human foraging and dietary strategies. Major expansion of the brain is associated with Homo rather than the Hominidae as a whole, and the energetic costs are likely to have forced a prolongation of growth rates and secondary altriciality. It is calculated here that modern human infants have energetic requirements approximately 9% greater than similar size apes due to their large brains. Consideration of energetic costs of brain allow the prediction of growth rates in hominid taxa and an examination of the implications for life-history strategy and foraging behaviour.

Animals↗
PubMed1989

Finite social space, evolutionary pathways, and reconstructing hominid behavior.

Changes in social behavior were a key aspect of human evolution, and yet it is notoriously difficult for paleobiologists to determine patterns of social evolution. By defining the limited number of distributional strategies available to members of each sex of any species and investigating the conditions under which they may occur and change, the social behavior of different hominid taxa may be reconstructed.

Animals↗